Thermosiphon circulator



June I3, 1944.- E REVARD i 2,351,544

THERMO-SYPHON CIRCULATOR Filed July 24, 1942 2 Sheets-Sheet 1 Inventor By and afa/ey 5ML/imm June 13, 1944. E. L. REVARD THERMO-SYPHON CIRULATOR Filed July 24, 1942 2 Sheets-Sheet 2 I nrw/lor M ;ymk/Fevaf@ Patented June 13, 1944 UNITED STlgl'l-S PATENT OFFlCEv-l THERMOSHHON CIRCULATOR Edward Lynn Revard, Ponca City, Okla. Application July 24, 1942, Serial No. 452,232

(c1. 13s-e2) 5 Claims.

The invention relates to improvements in therino-Siphon circulators, the primary object of the invention .being to provide arrangements of this character especially adapted for use is connection with the movement oi liquids, vapors or gases in areas wherein the conduits containing the same are exposed to freezing temperatures, to positively prevent sufficient stagnation of the liquids or gases during interruptions in operational movements thereof to allow of freezing.

Other important objects and advantages of the invention will be apparent from a reading of the following description taken in connection with the appended drawings, wherein for purposes of illustration preferred embodiments of the invention are shown.

In the drawings:

' Figure l is a general schematic vertical sec tional View of an installation in accordance with the present invention showing a conduit containing fluid such as a gas, a vapor or a liquid leading from a storage tank or source of fluid through an area exposed to freezing temperatures.

Figure 2 is an enlarged fragmentary horizontal sectional view taken through Figure l along the line 2-2 and looking downwardly in the direction of the arrows.

Figure 3 is an enlarged fragmentary Vertical sectional view taken through a modified form4 of installation.

Figure 4 is a similar View of a still further modiiied form of installation.

Figure 5 is a part sectional and elevational View showing a dua-l installation in accordance` with the present invention, wherein two different forms of circulators are used in the same installation, one to protectively circulate the fluid in the vertical line and the other to protectively circulate the iiuid in the horizontal line.

Referring in detail to the drawings, and iirst to the embodiment of the invention shown in Figures l and 2 of the drawings, the numeral 5 ygenerally designates a'tank or other source of fluid supply from which leads the protectively buried conduit 5 which is ylocated below ground level, and has a branch leading therefrom which has the portion 9 which is a thermo-Siphon circulator exposed above the ground to freezing temperatures.

The circulator 9 comprises a vertically elongated substantially closed loop conduit Il) having an outlet II for the fluid at a point outside of the freezing area, whereby the circulated fluid whether liquid, vapor, or gas is continued in circulation in the exposed areas of the circulator during periods when the contents of the conduit have no other means of movement. The loop conduit I0 is characterized by a vertical riser portion I2 which is equipped, in this instance, by a jacket I3 surrounding the riser and containing a heating medium entering it by the pipes I4 and I5, whereby the riser I2 is endowned with a temperature substantially more elevated than any other portion of the loop I0, so that the liquid or gas has a positive tendency in accordance with well known principles to rise in the riser l2 and to have its place taken at the lower end of the heater I3 by the subsiding cooler iiuid. By these actions the fluid circulates upwardly through the riser I2 to the highest point of the loop conduit Ill then starts downwardly in the conduit IQ so as to downwardly displace the cooler contents of the conduit, thereby causing motion of the fluid in the conduit Ill, the speed of which is determined by the amount of heat applied by the heater I3.

Referring now to the embodiment of the invention shown in Figure 3 of the drawings and which is generally designated 9a, this comprises also a duplex conduit forming a circulation loop and characterized by the riser conduit I2u which is heated by a jacket Illa supplied with heating medium by the pipes Illa and lila, the riser portion I2a being located partly below the ground level la and having its lower end portion connected as indicated by the numeral 8a with the conduit 6a leading from the tank or container of the liquid or gas to be circulated (not shown). In the instance of this embodiment the companion leg of the loop circuit comprises the vertical extension Ia of the conduit 6a and has at its upper end the outlet or return IIa. The riser I2a has a portion smaller in diameter than the leg Illa and enters the leg Ia at the point indicated by the numeral' I'I and rises spacedly therein as indicated by the numeral I8, to a point below the upper end of the leg Illa. In this embodiment the liquid or gas heated in the riser IZa by the heater Ia rises in the riser I2a and Causes the colder liquid or gas to displace the risen liquid or gas, so as to withdraw the liquid or gas from the conduit Ea and discharge the same at the outlet IIa.

Referring now to the embodiment of the invention shown in Figure 4 of the drawings, this form of circulator is generally designated by the numeral 9b and comprises the vertical riser conduit I2?? in which is inserted a heating medium pipe I3a. The upper end of the riser I2b connects with the upper end of the companion con- Vllower portion of the riser I2b by the heater I3a causes the liquid or gas in the riser to move upwardly toward the outlet IIb, while the colder v liquid or gas Ain the companion conduit IIlb` swbsides and tends to move into the lower end of the riser I2b and take the place of the risen warmer fluid, whereby a circulation is produced which acts to draw the liquid or gas from the conduit 6b and circulate the same continuously, while the heat is applied, to the outlet IIb which is connected to any desired destination or to the said tank or container.

It is characteristic of all of the described embodiments that maior portions of the circulators are exposed to the extreme low temperatures in the region of storage of the liquid or gas, while a minor portion thereof is subjected to heating, whereby an automatic thermo-Siphon circulation of the liquid or gas is produced, which positively prevents freezing of the liquid or gas in the tanks or containers.

Figure 5 of the drawings exemplifies employment of two circulators in accordance with the present invention in association with a solution tank. The circulator 9 has its conduit 8 connected at its lower end with a water supply pipe 6, with a cut-oil valve in the conduit 6. The 'upper end of the loop has the outlet conduit II which is provided with a cut-off valve 2|, the upper part of the loop rising into the upper part of the solution tank 22 which is supported in an elevated position by the standard 23, the portion of the loop between the valve 8 and the tank 22 being exposed to the freezing temperatures. The heater I3 is associated with the lower part of the leg I2 of the said loop with heating medium lines I4 and I5 extending away from the heater to a suitable source.

The solution tank discharge conduit 24 extends horizontally into a building 25 wherein the solution formed in the tank 22 is used or stored, the portion of the conduit between the tank and the building being exposed to freezing temperatures. To circulate the solution in the conduit 24 the same can be modified to provide the horizontal part 26, a depending vertical part 21 including a heater I3', and an angulated part 28 connecting the lower end of the vertical part 21 withthe remote end of the horizontal part 26. The arrangement keeps the solution circulating in the resultant loop even when the cut-ff valve 29 in the conduit 24 is closed, thereby preventing freezing of the solution in the conduit 24.

Although there are shown and described herein preferred embodiments of the invention, it is to be definitely understood that it is not desiredto limit the application of the invention invention, what l is to sub-freezing temperature and comprising av looped conduit for said fluid with a supply connection at one end from said source and an outlet from its opposite end, and heating means for the conduit adjacent the supply connection.

2. A thermo-Siphon circulator for a fluid from `a source of supply exposed to sub-freezing temperature; said circulator comprising a looped conduit for said uld with a supply connection at one end from said source and an outlet from its opposite end, and heating means for the conduit adjacent the supply connection, said conduit being in the form of a tubular loop having two interconnected legs, one of which constitutes the supply portion, said heating means consisting of a short pipe within said supply portion with pipe connection from a source of heat supply.

3. A thermo-Siphon circulator for a fluid from a source of supply; said circulator being exposed to sub-freezing temperature and comprising a conduit for said fluid with a supply connection at one end from said source and an outlet from its opposite end, and heating means for the conduit adjacent the supply connection, said conduit being in the form of a tubular loop having two legs one of which constitutes the supply portion, and said heating means'consisting of a jacket surrounding the supply portion, said jacket being heated from a source of heat.

4. A thermo-Siphon circulator for a fluid from a source of supply, said circulator being exposed to freezing temperature and comprising a riser connected in intake communication with said source, said riser having a portion elevated about the level of intake of the fluid, heating means applied to a lower portion of the riser to cause the fluid present in the riser to rise, and a complementary conduit leg connected in communication by top and bottom loops `with said riser, whereby cool iiuid from the source is flowed into said riser to take the place of the risen warmer iiuid in the riser, thus providing a continuous fluid circulation in the circulator, and an outlet from said riser and said leg for discharging fluid when desired.

5. A thermo-Siphon circulator for a fluid from a source of supply, said circulator comprising a looped conduit having a riser leg and a return leg connected in intake communication with said source, said riser leg having at least a portion elevated above the level of intake of the fluid and exposed to freezing, heating means applied to the lower portion of the riser leg to cause the iiuid present therein to rise, whereby cooler iiuid is owed into said riser leg to take the place of the risen warmer fluid in the riser leg, and an outlet with which said riser and Vsaid return leg are in communication for discharging the warmed iiuid from the circulator when required.

EDWARD LYNN REVARD. 

